The invention relates to a screw cap of the type for closing a bottle or the like.
DE 41 08 453 A1 reveals a screw cap of the respective type, whereby the inwardly directed catches are hook shaped in order that, when the screw cap is first screwed on to the outer thread of a bottle neck, the catches snap on behind a circumferential outer collar arranged on the bottle neck for security purposes. When screwing the screw cap off the bottle, the hook shaped catches keep the security ring back from the outer collar on the bottle neck, so that the break points formed of thin webs between the security ring and the cylindrical part of the screw cap break off, and thus the security ring remains behind on the bottle neck. It is thus assured that the bottle has not previously been opened, since when the cap is unscrewed the security ring is held back on the bottle neck in a loose manner. It is thus easy for anyone to recognize whether the bottle has already been opened once.
A disadvantage to this known screw cap is i:hat a relatively great torque is required when the hook shaped catches on the security ring are moved over the outer collar on the bottle neck. As a result of this increased torque there is a risk that the break points formed of thin webs between the safety ring and the cylindrical part of the screw cap will shear off, even as the cap is screwed on, so that the security ring then rests loosely on the neck of the bottle, just as in the case where the bottle has been opened for the first time and has then been closed again. The fact that the contents of the bottle have never been opened is therefore not recognizable or guaranteed.
The invention has the task of devising a screw cap of the respective type, whereby the danger of shearing off the break points between the cylindrical part of the screw cap and the security ring is decreased during the initial screwing on of the cap.
The basic concept of the teaching consists of connecting the cylindrical part of the screw cap and the security ring in a firm locking manner in the circumferential direction, but permitting its removal in the direction of the threading. By positively engaging the opposing edges of the cylindrical part and the security ring, great torques can be transferred without the opposing movement of the two parts, so that there is no danger that the break points that connect the security ring with the cylindrical part of the screw cap in the original condition can be sheared or torn off.
The projection and the recess are expediently at right angles, whereby a plurality of projections and recesses are expediently provided, preferably engaging with each other in meander shaped manner. The webs can basically be located at any desired position, that is, for example, where no projections and recesses engage each other. Expediently, the break points are located between circumferentially juxtaposed surfaces of projections and recesses. The break points can also be formed by means of webs arranged between the projections and recesses. The toothing expediently extends over the entire circumference.